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Wire rate vs non blocking switch

Hi all, i am often confused by these 2 terms. Please help me to understand them

 

  • if a switch is wire rate, does that implicitly means its non blocking
  • or is it due to non blocking that the switch is wire rate ?
  • is it possible that a switch is wire rate but not non-blocking ?
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In the context of switch performance, generally a non-blocking switch's interior bus/fabric offers enough bandwidth that meets, or exceeds, the aggregate bandwidth of all its ports.  However, even if that's true, some switch architectures can block traffic due to head-of-line blocking, i.e. congestion on one port blocks another uncongested port or ports.  (NB: "modern" switch architectures usually don't have HoL blocking as a possible issue.)

 

Also even if a switch is non-blocking, regarding its interior bandwidth, wire-speed/line-rate requires the switch's frame/forwarding support full bandwidth with minium size frame/packets.

 

So to recap, non-blocking really means there's sufficient bandwidth, wire-speed/line-rate really means frame/packet forwarding supports full bandwidth regardless of frame/packet sizes.

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